The candidate is a gastroenterologist with strong training in patient-oriented research methodology, and a proven commitment to the study of esophageal diseases, and eosinophilic esophagitis (EoE) in particular. The candidate's long-term career goal is to be an independently funded physician-scientist in the area of esophageal diseases leading a multidisciplinary translational research team bridging the clinic, endoscopy suite, pathology lab, and basic science lab. The candidate's short-term career goals for the K23 program are to: 1) acquire knowledge and skills in translational research techniques; 2) develop the professional skills to successfully lead a multidisciplinary research team; and 3) produce a critical mass of preliminary data and publications to support an R01 grant application and establish a program of independent research in EoE. The proposed research plan, career development activities, mentorship team, and institutional environment are all uniquely suited to assist the applicant in achieving these goals. The candidate's overall research goal is to better understand the epidemiology and pathogenesis of EoE in order to improve diagnosis and treatment. EoE is a rapidly emerging clinicopathologic entity defined by abnormal infiltration of eosinophils into the esophageal mucosa that leads to dysphagia, progressive esophageal stenosis, and food impaction. The specific goals of this research proposal are to validate our model of risk factors for diagnosis of EoE, and to assess the utility of serum levels of eotaxin-3 and IL-13 in diagnosis and monitoring of treatment of EoE. We will compare patients with newly diagnosed EoE to non-EoE controls, obtain baseline measures, reassess EoE patients after treatment, and also reassess untreated controls. The central premises to be tested are that: 1) clinical risk factors, coupled with non-invasive serum biomarkers, will lead to more accurate diagnosis of EoE; and 2) non-invasive biomarkers can be used to monitor treatment response. To support the candidate's career development, he will conduct a series of formal internships in selected basic science labs focusing on specific translational research techniques, as well as pursue advanced coursework and independent study in the areas of molecular techniques, biomarkers, and statistics as applied to public health and epidemiology. The mentorship and advising team, which includes internationally-recognized, independently-funded investigators with expertise in gastrointestinal epidemiology and translational team research (Sandler), esophageal diseases and translational research (Shaheen), cell and molecular physiology (Henning), and EoE pathogenesis and translational methods (Rothenberg), will guide Dr. Dellon's research and career development. The research environment including the Translational and Clinical Sciences Institute and Center for Gastrointestinal Biology and Disease at UNC provides a productive, collegial, and collaborative atmosphere in which to pursue the above research and training goals. At the conclusion of this program, Dr. Dellon will be positioned to be an independent physician-scientist leading a multidisciplinary translational research team.